in this research introduced the lapsus model as a runoff, erosion and sediment model in iran. this model for the first time has operatedin iran at kakhk paired catchment of gonabad. lapsus model is a landscape evolution model that can estimate the runoff, erosion and sediment at the four stage include: calculate the effective rainfall, runoff routing, calculate the capacity of sediment transpor...

a quantitative evaluation of the effects of contamination of soil with petroleum, on thesoil physical properties, is required for optimal soil and water resources management. theobjective followed in the present study was to investigate runoff generation in soilscontaminated with kerosene and gas oil. towards this end, variables of runoffcommencement, runoff coefficient, variations in runoff du...

Phosphorus loss in runoff from agricultural fields has been identified as an important contributor to eutrophication. The objective of this research was to determine the relationship between phosphorus (P) in runoff from a benchmark soil (Cecil sandy loam; fine, kaolinitic, thermic Typic Kanhapludult) and Mehlich III-, deionized water-, and Fe(2)O(3)-extractable soil P, and degree of phosphorus...

This study investigates the role of soil moisture on the threshold runoff response in a small headwater catchment in the Italian Alps that is characterised by steep hillslopes and a distinct riparian zone. This study focuses on: (i) the threshold soil moisture-runoff relationship and the influence of catchment topography on this relation; (ii) the temporal dynamics of soil moisture, streamflow ...

Phosphorus (P) in irrigation runoff may enrich offsite water bodies and streams and be influenced by irrigation water quality and antecedent soil surface conditions. Runoff, soil loss, and P fractions in runoff using reverse osmosis (RO) water or mixed RO and well water (RO/ Tap) were studied in a laboratory sprinkler study to evaluate water source effects on P transport. A top- or subsoil Port...

Differences in the properties of organic phosphorus (P) sources, particularly those that undergo treatment to reduce soluble P, can affect soil P solubility and P transport in surface runoff. This 2-yr field study investigated soil P solubility and runoff P losses from two agricultural soils in the Mid-Atlantic region after land application of biosolids derived from different waste water treatm...

Evaluation of phosphorus (P) management strategies to protect water quality has largely relied on research using simulated rainfall to generate runoff from either field plots or shallow boxes packed with soil. Runoff from unmanured, grassed field plots (1 m wide x 2 m long, 3-8% slope) and bare soil boxes (0.2 m wide and 1 m long, 3% slope) was compared using rainfall simulation (75 mm h(-1)) s...

Increased stormwater flows are a direct result of urbanization and the consequent increase in the proportion of land area under impervious surface. Due to its contribution to abnormally high stream flows and its role as a carrier of pollutants that degrade water quality, excess stormwater runoff has negative impacts on both terrestrial and aquatic ecosystems. In response to the increased magnit...

Understanding the basic runoff processes in the Ethiopian highlands is vital for effective management and utilization of water resources and soil conservation planning. An important question for judging effectiveness of conservation practices is whether runoff is affected by ecology (mainly type of crop) or topography (landscape). A study was conducted in the 113 ha watershed of Maybar, located...

Intensive residential use of insecticides has resulted in their ubiquitous presence as contaminants in urban surface streams. For pest eradication, urban hard surfaces such as concrete are often directly treated with pesticides, and wind/water can also carry pesticides onto hard surfaces from surrounding areas. This study expanded on previous bench-scale studies by considering pesticide runoff ...